Alright, it's been deployed
Play the game
The game worked before though, I'm looking to remove the old mods
Were the old mods installed with Vortex?
If so, uninstall them with Vortex
They were installed with NMM, and then I uninstalled NMM without deleting the old mods
There's your problem.
Never, ever, ever uninstall a mod manager without uninstalling the mods first.
The ONLY thing you can do at this point is...
1. PURGE your Vortex installed FONV mods,
2. Delete the Fallout New Vegas Data folder,
3. have steam reverify the files so it downloads a clean Data folder
4. Re-Deploy your mods in Vortex.
Using 'Verify integrity of game files' right?